Low profile clamp on GB?

[Aragorn]

So I'm hunting for a low profile .750 clamp on gas block that will fit under a rail with a 1.3" inner diameter. The only company to give dimensions is SLR.

http://slrrifleworks.com/index.php?route=product/product&path=57_103_104&product_id=123

So with some math we get this:

Forend I.D. = 1.3" = .65" per side

SLR Clamp on GB = .58 from centerline to bottom

.07" clearance

That's not much. That's between 1/16 and 3/32 on an inch. Is that enough when trying to account for barrel movement/whip while firing?

I asked Daniel Defense about their clamp on GB's and they said there's would not fit. I'm also not really wanting an adjustable GB. Which I think pretty much just leaves Vltor as I'm sure as hell not going to use a Yankee Hill.

Thoughts? Idea's? Solutions?

[RiverRat]

Can't speak to quality or dimensions, but here are three more options for you to research.

https://www.veriforcetactical.com/product/ar-15-low-profile-gas-block-clamp-style-steel/

http://www.tacticallink.com/Naroh-Arms-Low-Profile-Stainless-Steel-750-Gas-Block-With-Matte-Black-Nitride-Finish-for-AR15-AR10-Rifles.html

http://www.aimsurplus.com/product.aspx?item=XDI11013&name=Damage+Industries+AR15%2fM16+Gas+Block+Clamp-On+.750&groupid=590

[BoilerUp]

I've got a DD .625 clamp on underneath a Midwest Industries Lightweight M-LOK handguard (which I believe may also have a 1.3" ID) and it just barely clears the bottom and renders the M-LOK attachment points immediately underneath useless. Frankly, I can't see how anyone else is going to be much slimmer than the DD. I believe the .750 gas block is identical in its external dimensions. You might just want to try a DD anyway.

The only other option I could think of to try is Black Rain Ordnance (I can't vouch for it): https://www.primaryarms.com/Black_Rain_Ordnance_Low_Profile_Gas_Block_750_p/bro-lp-750.htm

[Aragorn]

I think I'm going to have to either A) scratch off the idea of using a clamp on or B) let it stick out past the forend.

[VIPER 237]

Why a clamp on vs a pinned or set screw? Those are usually slightly lower profile than the clamp on ones.

[Aragorn]

Accuracy purposes primarily. It's going to be used on more of a precision set up.

[Jerry R]

Question please ......... I'm not sure I understand how the version of gas block affects accuracy. Would really like to know - it may alter future builds. Thanks.

[John Hwang]

Using setscrews shouldn't be a problem in most cases. Just dimple the barrel and you should be good to go

[Aragorn]

Question please ......... I'm not sure I understand how the version of gas block affects accuracy. Would really like to know - it may alter future builds. Thanks.

From what I've read, pressure set screws can cause a slight bulge or tight spot in the bore. Supposedly some people have had excessive copper fouling in that area which would support that theory.

For me it's all just that. Theory based.

[SINNER]

I see no possible way a properly installed set screw gas block would cause a bore deformation. By that logic a clamp on block would also cause bore eccentricity. You are talking inch/lbs of torque on those small set screws.

[Aragorn]

Yeah I thought about that too. I guess I could kinda see it causing pressure as things got hot and expanded, the set screw would be the point where things were the tightest.

I just figured since I'm building for precision I'd explore the option if I found something that would fit.

[GOST]

It's a little bit of a different direction but another option is a Knights Armament Mod 2 upper. Their new gas system secures the gas block with a lock nut and no pins. They say it decreases gas leakage while increasing barrel rigidity.

[Aragorn]

It's a little bit of a different direction but another option is a Knights Armament Mod 2 upper. Their new gas system secures the gas block with a lock nut and no pins. They say it decreases gas leakage while increasing barrel rigidity.

Perhaps someday I'll own a Knights, but not going that way right now. Cool idea though.